A powder multi-stage mixing apparatus and method

Abstract

This invention belongs to the field of powder metallurgy material mixing technology, specifically a multi-stage powder mixing device and method. It utilizes the gas-solid fluidization phenomenon generated by powder at a certain flow rate and velocity, allowing the powder to be uniformly dispersed in a stable flow pipe. The dispersed powder is thoroughly mixed with atomized droplets, while a high-temperature airflow is blown in to dry the mixed powder, achieving a primary mixing effect. Subsequently, a high-pressure airflow blows the primary mixed powder into a spiral pipe for collision, achieving a secondary mixing effect. This invention's multi-stage powder mixing device has high powder production efficiency, introduces fewer impurities, and provides good protection for the powder surface morphology. The mixed alloy powder exhibits good uniformity and high dryness, and can be directly used for pressing and sintering.

Description

Technical Field

[0001] This invention relates to the field of powder metallurgy material mixing technology, specifically to a multi-stage powder mixing device and method. Background Technology

[0002] Powder metallurgy is a common method in alloy production. Mixing is a crucial step in a series of processes including mixing, pressing, sintering, and rolling. The most critical aspect of mixing is its uniformity, which directly affects the final product's performance. With increasingly stringent requirements for material performance, the drawbacks of existing mixing methods have become more apparent. For solid-solid mixing, since alloying elements are often added in trace amounts, the fine particle size of the powder makes it prone to agglomeration and the introduction of impurities, resulting in generally poor mixing uniformity. In solid-liquid mixing, existing methods often lead to clumping and the introduction of impurities, and the solid powder cannot fully contact the solution, further degrading the uniformity. For liquid-liquid mixing, accurate composition control is difficult, the powder is prone to oxidation, and pressure processing performance is relatively poor. These drawbacks ultimately result in alloy products with uneven particle size and low sintering activity, making it difficult to improve the overall performance of the alloy. Summary of the Invention

[0003] To address the problems existing in the prior art, the main objective of this invention is to propose a multi-stage powder mixing device and method.

[0004] To address the aforementioned technical problems, according to one aspect of the present invention, the present invention provides the following technical solution:

[0005] A multi-stage powder mixing device, comprising:

[0006] The flow stabilizing pipe and the spiral pipe are installed sequentially.

[0007] The flow stabilizing pipeline includes a horizontal flow stabilizing pipeline extending from the inlet end to the outlet end and a vertical flow stabilizing pipeline connected to the horizontal flow stabilizing pipeline. The inlet end of the flow stabilizing pipeline is provided with an inlet for adding matrix powder. An atomizing device is provided at the connection between the horizontal and vertical flow stabilizing pipelines to atomize the alloying raw materials to be mixed with the powder and send them into the flow stabilizing pipeline, thereby achieving one-time mixing of the matrix powder and the alloying raw materials. The inlet end of the flow stabilizing pipeline is provided with a high-temperature gas nozzle for blowing in high-temperature gas, so that the matrix powder added through the inlet and the alloying raw materials atomized by the atomizing device are fluidized and dried in the flow stabilizing pipeline, thereby achieving one-time mixing.

[0008] The spiral pipe is set horizontally, and its feed end is located on the pipe wall of the lower half of the vertical steady flow pipe. A high-pressure gas nozzle is set on the pipe wall of the lower half of the vertical steady flow pipe, which is directly opposite the feed end of the spiral pipe. This nozzle is used to blow the alloy powder that has been mixed once into the lower half of the vertical steady flow pipe into the spiral pipe to achieve secondary mixing.

[0009] As a preferred embodiment of the powder multi-stage mixing equipment described in this invention, the powder multi-stage mixing equipment further includes a powder collection bin, and the discharge end of the spiral pipe is connected to the powder collection bin.

[0010] In a preferred embodiment of the powder multi-stage mixing device of the present invention, the powder collection bin is provided with a discharge port.

[0011] In a preferred embodiment of the powder multi-stage mixing device of the present invention, both the horizontal and vertical flow stabilizing pipes have circular cross-sections.

[0012] In a preferred embodiment of the powder multi-stage mixing equipment described in this invention, the feed inlet is connected to a feeding device, which controls the powder supply speed and quantity.

[0013] In a preferred embodiment of the powder multi-stage mixing equipment described in this invention, the feeding device employs an electromagnetic vibrator, and the vibration frequency and amplitude are adjusted to control the powder feeding speed and quantity.

[0014] As a preferred embodiment of the powder multi-stage mixing equipment described in this invention, the atomizing device adopts an ultrasonic nano-level atomizer, and the diameter of the atomization range of its conical nozzle at the center of the pipe is 0.95 to 1.05 times the diameter of the horizontal steady flow pipe of the steady flow pipe.

[0015] As a preferred embodiment of the powder multi-stage mixing equipment described in this invention, the spiral radius of the spiral pipe is 20-30cm and the pitch is 25-30cm.

[0016] To solve the above-mentioned technical problems, according to another aspect of the present invention, the present invention provides the following technical solution:

[0017] A powder multi-stage mixing method, using the above-mentioned powder multi-stage mixing apparatus, includes the following steps:

[0018] S1. High-temperature gas is blown in through a high-temperature gas nozzle, causing the matrix powder added from the feed port to fluidize in the steady flow pipe. Then, it is microscopically and uniformly mixed with the alloying raw material atomized by the atomizing device in the steady flow pipe and dried to achieve one-time mixing.

[0019] S2. High-pressure gas injected through a high-pressure gas nozzle blows the alloy powder, which has undergone primary mixing, into a spiral pipe through a vertical flow stabilization pipe to achieve secondary mixing.

[0020] As a preferred embodiment of the powder multi-stage mixing method of the present invention, in step S1, the flow rate and flow rate of the high-temperature gas in the high-temperature gas nozzle are adjusted so that the matrix powder added from the feed port is fluidized in the horizontal steady flow pipe, and is uniformly mixed with the alloy raw material atomized by the atomizing device and dried.

[0021] In a preferred embodiment of the powder multi-stage mixing method of the present invention, in step S1, the atomizing device atomizes the solution of the alloying raw material dissolved in alcohol and sends it into the constant flow pipeline.

[0022] The beneficial effects of this invention are as follows:

[0023] This invention proposes a multi-stage powder mixing device and method. Utilizing the gas-solid fluidization phenomenon generated by powder at a certain flow rate and velocity, the powder can be uniformly dispersed in a stable flow channel. The dispersed powder is thoroughly mixed with atomized droplets, while a high-temperature airflow dries the mixed powder, achieving a primary mixing effect. Subsequently, a high-pressure airflow blows the alloy powder, which has undergone primary mixing, into a spiral channel for collision, achieving a secondary mixing effect. This invention's multi-stage powder mixing device has high powder production efficiency, introduces fewer impurities, and provides good protection for the powder surface morphology. The mixed alloy powder exhibits good uniformity and high dryness, making it suitable for direct pressing and sintering. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 This is a front view of the structure of the powder multi-stage mixing device of the present invention;

[0026] Figure 2 This is a rear view of the structure of the powder multi-stage mixing device of the present invention.

[0027] In the diagram, 1-atomizing device, 2-feed inlet, 3-feeding device, 4-high temperature gas nozzle, 5-horizontal steady flow pipe, 6-vertical steady flow pipe, 7-spiral pipe, 8-powder collection bin, 9-discharge outlet, 10-high pressure gas nozzle.

[0028] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0029] The technical solutions described below in conjunction with the embodiments will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] This invention proposes a multi-stage powder mixing device and method to solve the problem that the mixing methods of the prior art result in uneven particle size and low sintering activity in the prepared products, making it difficult to improve the overall performance of alloy products (such as molybdenum alloys).

[0031] According to one aspect of the present invention, the present invention provides the following technical solution:

[0032] A multi-stage powder mixing device, comprising:

[0033] The flow stabilizing pipe and the spiral pipe 7 are installed sequentially.

[0034] The flow stabilizing pipeline includes a horizontal flow stabilizing pipeline 5 extending from the inlet end to the outlet end and a vertical flow stabilizing pipeline 6 connected to the horizontal flow stabilizing pipeline. The inlet end of the flow stabilizing pipeline is provided with an inlet 2 for adding matrix powder. An atomizing device 1 is provided at the connection between the horizontal flow stabilizing pipeline 5 and the vertical flow stabilizing pipeline 6 for atomizing the alloying raw material to be mixed with the powder and sending it into the flow stabilizing pipeline to achieve one-time mixing of matrix powder and alloying raw material. The inlet end of the flow stabilizing pipeline is also provided with a high-temperature gas nozzle 4 for blowing in high-temperature gas, so that the matrix powder added through the inlet 2 and the alloying raw material atomized by the atomizing device 1 are fluidized and dried in the flow stabilizing pipeline to achieve one-time mixing.

[0035] The spiral pipe 7 is horizontally arranged, and its feed end is located on the lower half of the vertical steady flow pipe 6 of the steady flow pipe. A high-pressure gas nozzle 10 is provided on the lower half of the vertical steady flow pipe 6 directly opposite the feed end of the spiral pipe 7 (that is, the center of the opening of the high-pressure gas nozzle 10 on the lower half of the vertical steady flow pipe 6 is directly opposite the center of the opening of the feed end of the spiral pipe 7). This nozzle is used to blow the mixed powder that has undergone primary mixing into the lower half of the vertical steady flow pipe 6 of the steady flow pipe to the spiral pipe 7 for secondary mixing.

[0036] Preferably, the temperature of the high-temperature gas is 100–230°C; and the pressure of the high-pressure gas is 0.15–0.25 MPa.

[0037] Preferably, the multi-stage powder mixing equipment further includes a powder collection bin 8, with the discharge end of the spiral pipe 7 connected to the powder collection bin 8, and the powder collection bin 8 is provided with a discharge port 9. In order to ensure stable internal air pressure, a one-way vent valve is provided in the upper middle part of the powder collection bin 8, which ensures gas flow while preventing alloy powder from flowing out with the gas.

[0038] Preferably, both the horizontal flow stabilizing pipe 5 and the vertical flow stabilizing pipe 6 have circular cross-sections. The diameters of the cross-sections of the horizontal flow stabilizing pipe 5 and the vertical flow stabilizing pipe 6 may be equal or unequal.

[0039] Preferably, the feed inlet 2 is connected to a feeding device 3, which controls the powder supply speed and amount.

[0040] Preferably, the feeding device 3 uses an electromagnetic vibrator to adjust the vibration frequency and amplitude to control the powder feeding speed and amount.

[0041] Preferably, the atomizing device 1 can be a commonly used atomizing device in the art. The inventors have found that when an ultrasonic nano-level atomizer is used, and the diameter of the atomization range of its conical nozzle at the center of the pipe is 0.95 to 1.05 times the diameter of the horizontal flow stabilizing pipe, the primary mixing effect and the final mixing effect are better than when using other atomizing devices (such as ordinary pressure atomizers).

[0042] Preferably, the inventors found that when the spiral radius of the spiral pipe 7 is 20-30 cm and the pitch is 25-30 cm, the secondary mixing effect and the final mixing effect are better than those of spiral pipes using other parameters.

[0043] According to another aspect of the present invention, the present invention provides the following technical solution:

[0044] A powder multi-stage mixing method, using the above-mentioned powder multi-stage mixing apparatus, includes the following steps:

[0045] S1. High-temperature gas is blown in by high-temperature gas nozzle 4, so that the matrix powder added by feed port 2 is fluidized in the steady flow pipe, and then microscopically and uniformly mixed with the alloying raw material after atomization by atomization device 1 in the steady flow pipe and dried to achieve one-time mixing.

[0046] S2. The high-pressure gas injected through the high-pressure gas nozzle 10 blows the alloy powder that has been mixed once into the vertical steady flow pipe 6 into the spiral pipe 7. Due to inertia and centrifugal force, collisions will occur inside the powder and between the powder and the pipe wall to achieve secondary mixing.

[0047] Preferably, in step S1, the flow rate and flow rate of the high-temperature gas in the high-temperature gas nozzle 4 are adjusted so that the matrix powder added from the feed port 2 is fluidized in the steady flow pipe, and then microscopically and uniformly mixed with the alloying raw material atomized by the atomizing device 1 in the steady flow pipe and dried to achieve one mixing.

[0048] Preferably, in step S1, the atomizing device 1 atomizes the solution containing the alloying raw materials dissolved in alcohol and then sends it into the constant flow pipe.

[0049] Preferably, in step S2, the powder after secondary mixing enters the powder collection chamber 8, and the powder is discharged through the discharge port 9 to obtain a uniformly mixed alloy mixture.

[0050] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0051] The powder multi-stage mixing device used in each embodiment includes: a flow stabilizing pipe and a spiral pipe 7 arranged sequentially; the flow stabilizing pipe includes a horizontal flow stabilizing pipe 5 extending from the inlet end to the outlet end and a vertical flow stabilizing pipe 6 connected to the horizontal flow stabilizing pipe; the inlet end of the flow stabilizing pipe is provided with an inlet 2 for adding matrix powder; an atomizing device 1 is provided at the connection between the horizontal flow stabilizing pipe 5 and the vertical flow stabilizing pipe 6 for atomizing the alloying raw material to be mixed with the powder and sending it into the flow stabilizing pipe to achieve one-time mixing of powder and alloying raw material; the inlet end of the flow stabilizing pipe is also provided with a high-temperature gas nozzle 4 for blowing in high-temperature gas to atomize the matrix powder added through the inlet 2. The bulk powder and the alloying raw material atomized by the atomizing device 1 are fluidized and dried in the steady flow pipe to achieve primary mixing. The spiral pipe 7 is horizontally arranged, with its inlet end located on the lower half of the vertical steady flow pipe 6. A high-pressure gas nozzle 10 is installed on the lower half of the vertical steady flow pipe 6, directly opposite the inlet end of the spiral pipe 7 (i.e., the center of the opening of the high-pressure gas nozzle 10 on the lower half of the vertical steady flow pipe 6 is directly opposite the center of the opening of the inlet end of the spiral pipe 7). This nozzle blows the mixed powder that has undergone primary mixing into the lower half of the vertical steady flow pipe 6 into the spiral pipe 7 for secondary mixing. The temperature of the high-temperature gas is 200℃; the pressure of the high-pressure gas is 0.25MPa. The multi-stage powder mixing equipment also includes a powder collection chamber 8, with the outlet end of the spiral pipe 7 connected to the powder collection chamber 8. The powder collection chamber 8 is provided with an outlet 9. The horizontal steady flow pipe 5 and the vertical steady flow pipe 6 of the steady flow pipe both have circular cross-sections. The horizontal steady-flow pipe 5 and the vertical steady-flow pipe 6 have the same cross-sectional diameter. The feed inlet 2 is connected to a feeding device 3, which controls the powder supply speed and quantity. The feeding device 3 uses an electromagnetic vibrator; the vibration frequency and amplitude are adjusted to control the powder supply speed and quantity. The atomizing device 1 uses an ultrasonic nano-level atomizer; the diameter of the atomization range of its conical nozzle at the center of the pipe is 1.0 times the diameter of the horizontal steady-flow pipe. The spiral pipe 7 has a spiral radius of 25 cm and a pitch of 30 cm.

[0052] Example 1

[0053] A method for multi-stage mixing of powders includes the following steps:

[0054] S1. Dissolve 1.200g fructose, 10.80g TiH2, and 3.96g ZrH2 in 600mL of alcohol to prepare a solution. Pour the prepared solution into the atomizing device. Pour 1200g molybdenum powder into the feed inlet. Turn on the atomizing device, the feeding device, and the high-temperature gas nozzle. Adjust the vibration frequency and amplitude of the feeding device and the flow rate and flow of the high-temperature gas to make the molybdenum powder and alloying raw materials fluidized and dried in the steady flow pipe, thus achieving one-time mixing.

[0055] S2. Open the spiral pipe inlet and high-pressure gas nozzle. The airflow will carry the mixed powder that has been mixed once and form a spiral motion in the spiral pipe. The spiral flow will cause the gas speed to change continuously. Due to the action of inertia and centrifugal force, the powder inside and between the powder and the pipe wall will collide to achieve a secondary mixing effect. The powder passing through the spiral pipe will enter the powder collection chamber. The powder will be discharged through the discharge port to obtain a uniformly mixed molybdenum alloy mixture.

[0056] Example 2

[0057] A method for multi-stage mixing of powders includes the following steps:

[0058] S1. Dissolve 1.200g fructose, 6.400g TiH2, 0.980g ZrH2, 30.000g Ti(SO4)2, and 4.520g Zr(NO3)4 in 600mL of alcohol to prepare a solution. Pour the prepared solution into an atomizing device. Pour 1000g molybdenum powder into the feed inlet. Turn on the atomizing device, the feeding device, and the high-temperature gas nozzle. Adjust the vibration frequency and amplitude of the feeding device, as well as the flow rate and flow of the high-temperature gas, so that the molybdenum powder and alloying raw materials are fluidized and dried in the steady flow pipe, achieving one-time mixing.

[0059] S2. Open the spiral pipe inlet and high-pressure gas nozzle. The airflow will carry the mixed powder that has been mixed once and form a spiral motion in the spiral pipe. The spiral flow will cause the gas speed to change continuously. Due to the action of inertia and centrifugal force, the powder inside and between the powder and the pipe wall will collide to achieve a secondary mixing effect. The powder passing through the spiral pipe will enter the powder collection chamber. The powder will be discharged through the discharge port to obtain a uniformly mixed molybdenum alloy mixture.

[0060] Example 3

[0061] A method for multi-stage mixing of powders includes the following steps:

[0062] S1. Dissolve 0.96g carbon powder, 12.8g TiH2, and 1.96g ZrH2 in 200mL of alcohol to prepare a solution. Pour the prepared solution into the atomizing device. Pour 200g molybdenum powder into the feed inlet. Turn on the atomizing device, the feeding device, and the high-temperature gas nozzle. Adjust the vibration frequency and amplitude of the feeding device and the flow rate and flow of the high-temperature gas to make the molybdenum powder and alloying raw materials fluidized and dried in the steady flow pipe, thus achieving one-time mixing.

[0063] S2. Open the spiral pipe inlet and high-pressure gas nozzle. The airflow will carry the mixed powder that has been mixed once and form a spiral motion in the spiral pipe. The spiral flow will cause the gas speed to change continuously. Due to the action of inertia and centrifugal force, the powder inside and between the powder and the pipe wall will collide to achieve a secondary mixing effect. The powder passing through the spiral pipe will enter the powder collection chamber. The powder will be discharged through the discharge port to obtain a uniformly mixed molybdenum alloy mixture.

[0064] Example 4

[0065] A method for multi-stage mixing of powders includes the following steps:

[0066] S1. Dissolve 0.24g fructose, 6.0g Ti(SO4)2, and 0.904g Zr(NO3)4 in 150mL of alcohol to prepare a solution. Pour the prepared solution into the atomizing device. Pour 500g molybdenum powder into the feed inlet. Turn on the atomizing device, the feeding device, and the high-temperature gas nozzle. Adjust the vibration frequency and amplitude of the feeding device and the flow rate and flow of the high-temperature gas to make the molybdenum powder and alloying raw materials fluidized and dried in the steady flow pipe, thus achieving one-time mixing.

[0067] S2. Open the spiral pipe inlet and high-pressure gas nozzle. The airflow will carry the mixed powder that has been mixed once and form a spiral motion in the spiral pipe. The spiral flow will cause the gas speed to change continuously. Due to the action of inertia and centrifugal force, the powder inside and between the powder and the pipe wall will collide to achieve a secondary mixing effect. The powder passing through the spiral pipe will enter the powder collection chamber. The powder will be discharged through the discharge port to obtain a uniformly mixed molybdenum alloy mixture.

[0068] Comparative Example 1

[0069] The difference from Example 1 is as follows:

[0070] Without secondary mixing, the high-pressure gas nozzle on the vertical flow stabilization pipe is closed, and the powder from the first mixing is collected directly in the vertical flow stabilization pipe for subsequent testing.

[0071] Comparative Example 2

[0072] The difference from Example 1 is as follows:

[0073] Without mixing, the molybdenum powder is placed directly into a vertical, stable flow pipe, the atomizing device and high-pressure gas nozzle are turned on, and the mixed powder is collected at the outlet and tested.

[0074] Comparative Example 3

[0075] The difference from Example 1 is as follows:

[0076] Reduce the spiral radius of the spiral pipe to 15cm and reduce the pitch to 20cm.

[0077] The molybdenum alloy mixed powders prepared using the various embodiments and comparative examples were directly pressed and sintered, and the properties of the prepared molybdenum alloys are shown in Table 1.

[0078] Table 1 Properties of Molybdenum Alloys

[0079] Tensile strength / MPa Elongation / % Example 1 1328 9.80 Example 2 1038 8.56 Example 3 1167 9.25 Example 4 1205 8.35 Comparative Example 1 1150 7.50 Comparative Example 2 800 8.87 Comparative Example 3 1200 8.56

[0080] As shown in the table above, the four examples demonstrate that the mixing ratio in Example 1 yields alloys with better performance. All four examples exceed the alloy strength (approximately 1000 MPa) obtained by mixing with the same ratio using methods such as three-dimensional mixers and ball mills. Comparative Example 1 shows that the tensile strength of the material obtained through only one-stage mixing is already at a high level, and the second-stage mixing process is equally indispensable for improving material performance. Comparative Example 2 shows that the uniformity of the alloy powder is not significantly improved by only two-stage mixing, requiring both mixing processes. Comparative Example 3 shows that there is a suitable range for the geometric parameters of the spiral pipe; a spiral radius of 20–30 cm and a pitch of 25–30 cm result in better mixing than other parameters.

[0081] This invention utilizes the gas-solid fluidization phenomenon generated by powder under certain flow rates and speeds, allowing the powder to be uniformly dispersed in a stable flow channel. The dispersed powder is then thoroughly mixed with atomized droplets, while a high-temperature airflow is blown in to dry the mixed powder, achieving a primary mixing effect. Subsequently, a high-pressure airflow blows the primary mixed powder into a spiral channel for collision, achieving a secondary mixing effect. This invention's multi-stage powder mixing equipment exhibits good sealing performance, introduces fewer impurities, and provides good protection for the powder surface morphology. The mixed powder exhibits good uniformity and high dryness, making it suitable for direct pressing and sintering.

[0082] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A multi-stage powder mixing device, characterized in that, include: The flow stabilizing pipe and the spiral pipe are installed sequentially. The flow stabilizing pipeline includes a horizontal flow stabilizing pipeline extending from the inlet to the outlet and a vertical flow stabilizing pipeline connected to the horizontal flow stabilizing pipeline. The inlet of the flow stabilizing pipeline is equipped with an inlet for adding matrix powder. An atomizing device is installed at the connection between the horizontal and vertical flow stabilizing pipelines to atomize the alloying material to be mixed with the matrix powder and then feed it into the flow stabilizing pipeline, achieving a single mixing of the matrix powder and the alloying material. The atomizing device uses an ultrasonic nano-level atomizer, and the diameter of the atomization range of its conical nozzle at the center of the pipeline is 0.95 to 1.05 times the diameter of the horizontal flow stabilizing pipeline. The inlet of the flow stabilizing pipeline is equipped with a high-temperature gas nozzle for blowing in high-temperature gas, causing the matrix powder added through the inlet to fluidize within the horizontal flow stabilizing pipeline, where it is microscopically and uniformly mixed with the alloying material atomized by the atomizing device and then dried, achieving a single mixing. The spiral pipe is set horizontally, with its feed end located on the pipe wall of the lower half of the vertical steady flow pipe. A high-pressure gas nozzle is installed on the pipe wall of the lower half of the vertical steady flow pipe directly opposite the feed end of the spiral pipe. This nozzle is used to blow the alloy powder that has entered the lower half of the vertical steady flow pipe and undergone primary mixing into the spiral pipe for secondary mixing.

2. The powder multi-stage mixing equipment according to claim 1, characterized in that, The multi-stage powder mixing equipment also includes a powder collection bin, with the discharge end of the spiral pipe connected to the powder collection bin.

3. The powder multi-stage mixing equipment according to claim 2, characterized in that, The powder collection bin is equipped with a discharge port.

4. The powder multi-stage mixing equipment according to claim 1, characterized in that, Both the horizontal and vertical flow stabilizing pipes have circular cross-sections.

5. The powder multi-stage mixing equipment according to claim 1, characterized in that, The feed inlet is connected to a feeding device, which controls the powder supply speed and amount.

6. The powder multi-stage mixing equipment according to claim 1, characterized in that, The feeding device uses an electromagnetic vibrator, and the vibration frequency and amplitude are adjusted to control the powder feeding speed and amount.

7. A method for multi-stage powder mixing, using the multi-stage powder mixing apparatus according to any one of claims 1-6, characterized in that, Includes the following steps: S1. High-temperature gas is blown in through a high-temperature gas nozzle, causing the matrix powder added from the feed port to fluidize in the steady flow pipe. Then, it is microscopically and uniformly mixed with the alloying raw material atomized by the atomizing device in the steady flow pipe and dried to achieve one-time mixing. S2. High-pressure gas injected through a high-pressure gas nozzle blows the alloy powder, which has undergone primary mixing, into a spiral pipe through a vertical flow stabilization pipe to achieve secondary mixing.

8. The powder multi-stage mixing method according to claim 7, characterized in that, In step S1, the flow rate and volume of the high-temperature gas in the high-temperature gas nozzle are adjusted so that the matrix powder added from the feed port is fluidized in the horizontal steady flow pipe, and is uniformly mixed with the alloy raw material atomized by the atomizing device and dried.

9. The powder multi-stage mixing method according to claim 7, characterized in that... In step S1, the atomizing device atomizes the solution of the alloying raw material dissolved in alcohol and sends it into the constant flow pipeline.

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